[FRIAM] Rugged fitness landscapes

[Jochen Fromm]

Yes, his work contains interesting ideas. I especially
like the appealing idea of correlating interdependencies 
in the genotype with the ruggedness of fitness landscapes, 
although it is probably to simple. Are interdependencies 
between modules in the genotypes a reason why small changes
in the genotype could have large effects on reproduction 
rates ? It seems plausible, but hard to prove.

The fitness function depends in general on the 
success of the phenotype (reproduction rates), and the 
relationship between genotype and phenotype is very 
complex and non-linear. The fitness of a phenotype 
is easy to determine, but hard to calculate from the 
genotype. This is similar to NP-complete problems: 
the quality of a solution is easy to verify, but the
solution itself is hard to calculate. Therefore it is 
probably hard to say how rugged the fitness landscape is 
dependent on changes in the genotype, because the fitness 
is an unpredictable emergent property of the whole system, 
including the environment. 

One recent concept in this area seems to be "Epistasis"
http://en.wikipedia.org/wiki/Epistasis

Epistasis and Shapes of Fitness Landscapes
http://arxiv.org/abs/q-bio.PE/0603034 

-J.